Powered window air filter

ABSTRACT

The present disclosure relates to powered window air filters. More particularly, it relates to air filter systems capable of use in a window opening. Some embodiments relate to an adjustably sized air filter. Some embodiments include a filter assembly including filter media and a fan and/or control unit that forces air through the filter media in the filter assembly.

TECHNICAL FIELD

The present disclosure relates to powered air filters. Moreparticularly, it relates to powered air filter systems capable of use ina window opening.

BACKGROUND

Windows are available in a large variety of sizes and can includevertically or horizontally operable sashes to provide air flow betweenan exterior and an interior of a building structure. Occupants of abuilding structure often desire opening windows to let fresh air into aninterior of a home, business, or otherwise enclosed space. However, inmany locations, such as highly populated areas of China, the outside airis more contaminated than the indoor air. Novel filtering solutions areneeded to let the fresh aspects of the outdoor air in without letting inthe pollution or contaminants. Outdoor contaminants may include largerparticles such as pollen, dust, and mold spores and smaller particlessuch as those forming PM_(2.5), bacteria, and viruses. Gaseous outdoorpollutants such as odors, NO_(x), SO₂, ozone, and others may also be ofconcern in some locations.

SUMMARY

The inventors of the present disclosure recognized that, in light of theabove, a need exists for a powered air filter that protects users fromair quality contaminants, allows fresh air get into the home throughwindows, can be easily installed and used by consumers, is versatile tofit in most locations, and/or has minimal impact on lighting andvisibility. In some embodiments, the powered air filter is a window airfilter. Powered air filters have various benefits, at least one of whichis that they provide more or increased air flow into a room than anunpowered (passive) air filter.

The inventors of the present disclosure invented various embodiments ofair filters, methods of making air filters, and methods of using airfilters.

Some embodiments relate to a window air filter comprising a filterassembly including filter media; and a fan and/or control unit thatforces air through the filter media in the filter assembly. In someembodiments, the fan and/or control unit comprises: a housing; a controlmodule; a vent; and a motor.

In some embodiments, the housing is at least one of u-shaped and/orc-shaped. Some embodiments further comprise an end cap. In someembodiments, the filter assembly is at least one of flexible,adjustable, and/or extendible.

Some embodiments further comprise an internal connector between the endcap and the fan and/or control unit. In some embodiments, the internalconnector provides an outward pushing force when the window air filteris installed in a window. In some embodiments, the internal connectorincludes at least one of a spring-loaded feature or a telescopingfeature. In some embodiments, the air filter further includeselectronics. Some embodiments further include an anchoring device.

In some embodiments, the filter media is replaceable within the filterassembly and/or wherein the filter assembly is replaceable. In someembodiments, the filter media is at least one of moisture-resistant,moisture-repellant, electrostatically charged, an electret nonwoven web,and/or not electrostatically charged. In some embodiments, the filtermedia includes at least one of carbon, activated carbon, a nonwoven, athermoplastic, a thermosetting material, a porous foam, fiberglass,paper, a high loft spunbound web, a low loft spunbound web, a meltblownweb, and/or bi-modal fiber diameter meltblown media. In someembodiments, the filter media is pleated. In some embodiments, thefilter media is at least one of self-supporting and non-self-supporting.

Some embodiments relate to a kit including an air filter as describedabove or herein and a cutting device capable of cutting the filter mediato a desired size.

Some embodiments relate to a kit including an air filter as describedabove or herein and an attachment device capable of permanently orsemi-permanently attaching the air filter to a window. In someembodiments, the attachment device is at least one of a nail, a screw, ahook, an adhesive, and/or an adhesive backed interlocking strip.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of an exemplary powered air purifier or filter inaccordance with principles of the present disclosure;

FIG. 2A is a cross-sectional view of an exemplary powered air purifieror filter in accordance with principles of the present disclosure;

FIG. 2B is a cross-sectional view of another exemplary powered airpurifier of filter in accordance with principles of the presentdisclosure;

FIG. 3A is a top view of the window air purifier of FIG. 2A;

FIG. 3B is a top view of the window air purifier of FIG. 2B;

FIGS. 4A-4C are perspective views of an exemplary window air purifier orfilter for installation in a vertically opening window in accordancewith principles of the present disclosure; and

FIG. 5A-5B are perspective views of an exemplary window air purifier orfilter for installation in a horizontally opening window in accordancewith principles of the present disclosure.

DETAILED DESCRIPTION

Various embodiments and implementations will be described in detail.These embodiments should not be construed as limiting the scope of thepresent application in any manner, and changes and modifications may bemade without departing from the spirit and scope of the embodiments andimplementations. For example, many of the embodiments, implementations,and examples are discussed with specific reference to window airfilters, but these should not be construed to limit the applicationscope to this one exemplary implementation. Further, only some end useshave been discussed herein, but end uses not specifically describedherein are included within the scope of the present application. Assuch, the scope of the present application should be determined by theclaims.

One exemplary embodiment of an air purifier or filter 20, in accordancewith principles of the present disclosure, is illustrated in FIG. 1. Insome embodiments, the air purifier or filter can be used in a window.The air purifier 20 of FIG. 1 includes a fan/control unit 22, a filterassembly 24, and an end cap 26. In general terms, the air purifier 20 iscapable of fitting into a window to filter impurities from the outdoorair to make it cleaner upon its exit from the air purifier into theindoors where people will breathe the cleaner air. In some embodiments,the fan 22 can be a low profile fan that draws air in through the filterassembly 24 and discharges the cleaned air to the indoor environment. Insome embodiments, the low profile design delivers purified outdoor airto the indoors without blocking a significant portion of the windowarea. In some embodiments, the low profile window air purifier 20 can beinstalled on a window ledge, fill the entire gap across the ledge,and/or provide a self-sealing construction to the window frame and sash.In some embodiments, the window air purifier 20 can be employed inhorizontal or vertical sliding multi-part windows.

In some embodiments, the fan/control unit 22 includes a housing 40,control modules 42, a vent 44, a plug 46, and a motor 48. In someembodiments, the fan/control unit 22 and the end cap 26 are rigidstructures, although they may include gaskets or other soft or rubberymaterials to provide improved air seals and gripping to the windowstructure surfaces. In some embodiments, the filter assembly 24 isinherently flexible, due to the choice of materials, the geometry of thefilter media 28, or both. In some embodiments, the filter assembly 24 isan elongated, adjustable-length assembly, as described in greater detailbelow. In some embodiments, an internal connector 30 may be included toextend between the fan/control unit 22 and the end cap 26. In someembodiments, the connector 30 is adjustable in a longitudinal directionbetween the fan/control unit 22 and the end cap 26. In some embodiments,the connector 30 can provide structural support for the window airpurifier 20 and may help maintain the dimensional integrity of thewindow air purifier 20 in use, particularly by providing compressionstrength. In some embodiments, the connector 30 may use spring-loaded,telescoping features, which could provide a constant outward pushingforce when the window air purifier 20 is installed in a window. In someembodiments, an outward pushing force could help the window air purifier20 remain installed in a variety of situations.

In some embodiments, the air filter and/or fan/control unit includeselectronics of a type generally known. Some exemplary electronics thatcan be used in the air filters described herein include, for example,sensors for temperature, humidity, particulate matter (e.g. PM2.5),VOC's, other gases or pollutants (e.g., ozone, etc.). In someembodiments, the onboard electronic controls could turn the air filterand/or fan on or off and/or could adjust the fan speed depending oninput from any of these sensors. Some embodiments could additionally oralternatively include wireless communication (e.g. wi-fi) so that theproduct could be remotely monitored or controlled. In some embodiments,the air filter could interact with other devices. In one exemplaryembodiments, the air filter could communicate with a user's smart phone.In another exemplary embodiment, the air filter could incorporate oraccess data from other sources (e.g. obtain local air qualitymeasurement data and modify its operation based on the received data).

The window air purifier 20 of FIG. 1 can include various filterassemblies. In some embodiments, the filter media 28 is exposed to the“dirty” air outside the window and is sealed to the air inside of thewindow. With additional reference to FIGS. 3A and 3B, in someembodiments, air flows from outside the window, through the filter media28, into the fan/control unit 22, and into the room through the vents44. As illustrated in FIGS. 2A-2B, in some embodiments, the filter media28 a, 28 b can be formed as a flat sheet. In some embodiments, thefilter media 28 a, 28 b can extend along the entire length of the filterassembly 24. In some embodiments, the filter media 28 is replaceable. Insome embodiments, the entire filter assembly 24 is sold as a singlereplaceable unit. In some embodiments, only the filter media 28 of thefilter assembly 24 is sold as the replaceable item, and the filterhousing 32 is considered permanent.

With reference to FIGS. 2A and 2B, in some embodiments, the filterassembly 24 includes a filter housing 32. In some embodiments, thefilter housing 32 can be C-shaped or U-shaped in cross section. In someembodiments, the shape, along with the internal open cavity formed bythe filter housing 32, provides some flexibility to the filter assembly24. In some embodiments, the filter housing 32 can be made of plastic,for example. Even a moderately thick plastic filter housing 32, in a C-or U-shaped geometry, will provide some flexibility. In someembodiments, the flexibility of the filter housing 32 can be useful inhelping to seal the filter assembly 24 to the window “W” when the filteris pinched between the window sash and the window frame during use. Insome embodiments, the filter housing 32 can include an outer cover 34and an inner shell 36. In some embodiments, flexibility may also beimparted through the selection of materials for the filter assembly 24,for example the use of thick (e.g. 5-25 mm) expanded polyethylene foam,or the inclusion of other gasket or weather-stripping materials can beused. In some embodiments, the outer shell 34 may be rigid or non-rigid.In some embodiments, the particular filter media 28 selected for thewindow air purifier 20 can be particularly suited have particulardesired characteristics described herein. In some embodiments, thefilter media 28 is preferably constructed from moisture-resistantmaterials and may optionally include additional layers or features tospecifically block or repel water, such as rain. In some embodiments, anelectrostatic charge is optionally imparted into or on to material(s) ofthe filter media 28. An electrostatically charged media 28 may be used,of which many grades are available, and many of which offer highefficiency with low pressure drop. In some embodiments, the filter media28 can be an electret nonwoven web. Electrostatic charge can be impartedto the filter media 28 in a variety of ways as is well known in the art,for example by hydrocharging, corona charging, etc. (e.g., as describedin U.S. Pat. No. 7,947,142 (mentioned above)). In other embodiments, thefilter media 28 is not electrostatically charged. Additionalmulti-functional media grades, which incorporate activated carbon orother materials for purifying gas-phase pollutants, may also beincorporated into the filter structure.

FIGS. 2A and 3A illustrate one exemplary embodiment of a filter media 28a including a nonwoven web media. In some embodiments, the filter media28 a can be constructed, for example, from nonwoven fibrous media formedof thermoplastics or thermosetting materials such as polypropylene,linear polyethylene and polyvinyl chloride. Other suitable, non-limitingmaterials for the filter media include porous foams, nonwovens, papers,fiberglass, or the like. In some embodiments, the filter media 28comprises a filter media that attracts and captures dust, allergens suchas pollen and mold spores, and fine particle pollution from the outdoorair.

In some embodiments, other nonwoven webs useful with the filter media 28a can be a high loft spunbond web, such as described, for example, inU.S. Pat. No. 8,162,153 to Fox et al., the entire teaching of which isincorporated herein by reference. In other embodiments, the filter media28 a can be a low loft spunbond web, such as those described in U.S.Pat. No. 7,947,142 to Fox et al., the entire teaching of which isincorporated herein by reference. In yet other embodiments, nonwovenwebs useful with the filter media 28 a are generated by other techniquesand/or have other characteristics, such as the meltblown nonwoven websdisclosed in U.S. Pat. No. 6,858,297 to Shah et al., the entire teachingof which is incorporated herein by reference). Other non-limitingexamples of useful nonwoven web formats include bi-modal fiber diametermeltblown media such as those described in U.S. Pat. No. 7,858,163, theentire teaching of which is incorporated herein by reference.

In some embodiments, the filter media 28 can alternatively be a pleatedfilter media 28 b, as illustrated in FIGS. 2B and 3B, including at leasta portion that has been folded to form a configuration comprising rowsof generally parallel, oppositely oriented folds. In some embodiments,pleats can be formed in the filter media 28 b using various methods andcomponents as are well known in the art, e.g., to form a pleated filterfor use in applications such as air filtration., for example thosedescribed in U.S. Pat. No. 6,740,137 to Kubokawa et al. and U.S. Pat.No. 7,622,063 to Sundet et al., the entire teachings of both of whichare incorporated herein by reference. FIGS. 2B and 3B illustrate anexemplary pleated filter media 28 b. In one embodiment, the pleatedfilter media 28 b extends only partially along the filter assembly 24,as illustrated in FIG. 3B. In some embodiments, the pleated filter media28 b may be difficult to cut linearly to fit an entire length of thefilter assembly 24. In some embodiments, the filter assembly 24 may besealed at the point where the filter media 28 b terminates, and the restof the filter assembly 24 length may be cut to the desired length forinstallation: it is essentially dead space. In some embodiments, thefilter media 28 can consist of the filter media or web alone or caninclude one or more additional components or structures applied orassembled to the filter media 28. The filter media 28 of the assembly 24can be self-supporting or non-self-supporting. Where the filter media 28consists of the filter media or web and a support structure, the filtermedia 28 can be non-self-supporting with the addition supportingstructure rendering the filter media 28, as a whole, to beself-supporting. As used herein, the term “self-supporting filter mediaor web” can describe at least one of the following conditions: (1) afilter media or web that is deformation resistant without requiringstiffening layers, adhesive or other reinforcement in the filter mediaweb; or (2) the filter media generally maintains its shape whensubjected to an airstream as described, for example, in U.S. Pat. No.7,169,202 to Kubokawa, the entire teachings of which are incorporatedherein by reference; or (3) a web or media having sufficient coherencyand strength so as to be drapable and handleable without substantialtearing or rupture. As used herein, the term “non-self-supporting” candenote an air filter media that is not capable, in the absence of asupport frame and/or a support grill, of withstanding the forcesencountered due to typical air flow.

The present window air purifiers or filters 20 can be useful inprotecting users from outside air quality contaminants As discussedabove, an electrostatically charged filter media 28 may be used.Additional multi-functional media grades, which may incorporateactivated carbon or other materials for purifying gas-phase pollutants,may also be incorporated into the filter assembly 24. The use of apowered fan unit 22 should provide more airflow into a room than anyunpowered (passive) window filter. It will also likely provide moreairflow than an open window under calm wind conditions. By further usinga low pressure drop web enabled by the electrostatic charging,additional airflow improvements and reductions in fan power consumptioncan be achieved.

FIGS. 4A-4C illustrate an exemplary installation process of the windowair purifier or filter 20 in a vertically opening window 80. First, thefilter media 28 is cut to length using a cutting utensil 82 such as aknife, heavy duty scissors, or similar object. The cut does not have tobe perfectly straight, because the end cap 26 attachment provides someroom for a non-straight cut. The filter media 28 is attached to thefilter assembly 24 between the fan/control unit 22 and the end cap 26,and then the entire window air purifier 20 is placed in a partially openwindow. For a vertical sliding window 80, as illustrated in FIGS. 4A-4C,the window air purifier 20 is positioned on the lower sill.

For a horizontal sliding window 180, as illustrated in FIGS. 5A-5B, thewindow air purifier 20 is positioned in a vertical orientation with thefan housing 30 on the bottom. In some embodiments, a pushing force frominternal rods or spring-loaded product 30 (see, e.g., FIG.1) provides aholding force to the window frame in either orientation. The window isclosed the rest of the way onto the window air purifier 20, and thecontact between the window sash and the window air purifier 20 providesa seal to close any gaps that might allow leakage from the outside tothe inside. In some embodiments, remaining small gaps may be avoided bythe use of a piece of foam, weather-stripping, etc. In addition, arestraining strap or other component (not shown) may be optionallyincluded and attached to prevent the window air purifier 20 fromdislodging and falling out of the window 80, 180 opening.

In some embodiments, the air filters of the present disclosure includean anchoring device that ensures that the air filter does not fall outof the window. The anchoring device can be any known such deviceincluding, for example, a strap that connects the air filter to a wallor other permanent or stable structure in a building, room, home, oroffice. The anchoring device is optional and present in some embodimentsthat would benefit from this enhanced security feature. For example, inthe US, most users of window air filters live in single family homes. Inmost instances, if the window air filter falls out of the window, itwill probably land in a bush, and it is extremely unlikely to hurtsomeone. In contrast, in urban environments or highly populatedcountries, like China, for example, many people live in high riseapartments. If the window air filter falls out of a window, the problemcould be more significant. In some instances, the window air filtercould harm people or property.

The air filters of the present disclosure can be placed in any desiredframe or housing. Some exemplary frames are described in, for example,U.S. Patent Application No. 62/041496 and 62/041,499, both of which areincorporated in their entirety herein. The air filter media can come inroll form, such as, for example, that described in U.S. PatentApplication No. 62/041,500, the entirety of which is incorporatedherein. The air filter assembly or media of U.S. Pat. No. 62/206,928 canbe used in the air filters of the present disclosure.

The terms first, second, third and the like in the description and inthe claims, are used for distinguishing between similar elements and notnecessarily for describing a sequential or chronological order. It is tobe understood that the terms so used are interchangeable underappropriate circumstances and that the embodiments of the inventiondescribed herein are capable of operation in other sequences thandescribed or illustrated herein.

All of the references mentioned herein are incorporated by reference intheir entirety. Moreover, the terms top, bottom, over, under and thelike in the description and the claims are used for descriptive purposesand not necessarily for describing relative positions. It is to beunderstood that the terms so used are interchangeable under appropriatecircumstances and that the embodiments of the invention described hereinare capable of operation in other orientations than described orillustrated herein.

The recitation of all numerical ranges by endpoint is meant to includeall numbers subsumed within the range (i.e., the range 1 to 10 includes,for example, 1, 1.5, 3.33, and 10).

Those having skill in the art will appreciate that many changes may bemade to the details of the above-described embodiments andimplementations without departing from the underlying principlesthereof. Further, various modifications and alterations of the presentinvention will become apparent to those skilled in the art withoutdeparting from the spirit and scope of the invention. The scope of thepresent application should, therefore, be determined only by thefollowing claims and equivalents thereof.

1. A window air filter comprising: a filter assembly including filtermedia; and a fan and/or control unit that forces air through the filtermedia in the filter assembly.
 2. The window air filter of claim 1,wherein the fan and/or control unit comprises: a housing; a controlmodule; a vent; and a motor.
 3. The window air filter of claim 2,wherein the housing is at least one of u-shaped and/or c-shaped.
 4. Thewindow air filter of claim 1, further comprising an end cap.
 5. Thewindow air filter of claim 4, further comprising: an internal connectorbetween the end cap and the fan and/or control unit.
 6. The window airfilter of claim 5, wherein the internal connector provides an outwardpushing force when the window air filter is installed in a window. 7.The window air filter of claim 5, wherein the internal connectorincludes at least one of a spring-loaded feature or a telescopingfeature.
 8. The window air filter of claim 1, wherein the filterassembly is at least one of flexible, adjustable, and/or extendible. 9.The window air filter of claim 1, wherein the filter media isreplaceable within the filter assembly and/or wherein the filterassembly is replaceable.
 10. The window air filter of claim 1, whereinthe filter media is at least one of moisture-resistant,moisture-repellant, electrostatically charged, an electret nonwoven web,and/or not electrostatically charged.
 11. The window air filter of claim1, wherein the filter media includes at least one of carbon, activatedcarbon, a nonwoven, a thermoplastic, a thermosetting material, a porousfoam, fiberglass, paper, a high loft spunbound web, a low loft spunboundweb, a meltblown web, and/or bi-modal fiber diameter meltblown media.12. The window air filter of claim 1, wherein the filter media ispleated.
 13. The window air filter of claim 1, wherein the filter mediais at least one of self-supporting and non-self-supporting.
 14. Thewindow air filter of claim 1, further including electronics.
 15. Thewindow air filter of claim 1, further comprising: an anchoring device.16. A kit, comprising: an air filter of claim 1; and a cutting devicecapable of cutting the filter media to a desired size.
 17. A kit,comprising: an air filter of claim 1; and an attachment device capableof permanently or semi-permanently attaching the air filter to a window.18. The kit of claim 17, wherein the attachment device is at least oneof a nail, a screw, a hook, an adhesive, and/or an adhesive backedinterlocking strip.